ZEOLITAS NATURALES DE DIFERENTES YACIMIENTOS CUBANOS: COMPOSICIÓN Y ESTABILIDAD QUÍMICA Y TÉRMICA

A comparative study on the thermal and chemistry stability in acid and basic media and other properties of the natural zeolites of the Cuban deposits of Palmarito de Cauto, San Andres and Tasajera to contribute to get bases for a selection suitable for their applications and development of materials with new properties is presented. The obtained results allow outlining that in the deposit of Palmarito de Cauto the mordenite zeolite phase type prevails, while in Tasajera the clinoptilolite-heulandite and in San Andres deposit a mixture of clinoptilolite-heulandite and mordenite exists. All three of them are classified as calcic zeolites due to their cationic composition. The zeolites both of Palmarito de Cauto and San Andres, in this same order, are more thermally stable that Tasajera zeolte. The three zeolites showed to be more stable under the basic treatments (NaOH up to 5 mol/L) that the acids (HCL up to 3 mol/L) applied during 4h, highlighting the lightly superior stability in acid media to the Palmarito de Cauto zeolite. These allow the use of controlled acid treatments (until 3 mol/L of HCL) to obtain its acid forms without their structure collapses, of interest to increase their acidity for catalytic use, to clean its surface and cavities to increase the effective superficial area.